Nebulizer

ABSTRACT

A nebulizer having an elongate housing supporting an air nozzle in aspirating relation to a liquid nozzle in an interior chamber of the housing to vaporize the liquid. Baffle discs each having a chordal section removed therefrom are placed in parallel spaced relation in the chamber substantially transverse to the direction of vapor flow in the chamber. The openings formed by the chordal sections of adjacent discs are non-aligned causing the vapor flow to follow a tortuous path, and impinge upon a baffle surface, collapsing larger liquid droplets in the vapor which collect in the chamber. A liquid flow control valve in one position connects the liquid nozzle to the accumulated liquid in the chamber, or to an external reservoir, and in a second position, to an exterior source of liquid.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is in the field of atomizers or nebulizers for producinga vapor of controlled composition that is useful as a medicant anddiagnostic inhalant, in humidification, as well as in other uses.

2. Description of the Prior Art

Atomizers or nebulizers for producing a fine mist or vapor are wellknown to the art and are well documented over the years by issuedpatents. The art has been striving to provide a simple yet effectivenebulizer and various combinations of atomizing devices and baffles havebeen used to produce a uniform mist or vapor. However, the flexibilityof operation is limited in the prior art devices and the baffleefficiency has not been entirely satisfactory.

SUMMARY OF THE INVENTION

An elongate, tubular housing supports an air nozzle at one end toconduct air flow under pressure longitudinally of a chamber interior ofthe housing. A liquid nozzle is supported in aspirating relation to theair nozzle in the chamber and is in communication with a liquid supply,the liquid being aspirated and vaporized by air flow through the airnozzle. A liquid flow control member, or valve, in one position connectsthe liquid nozzle to accumulated liquid in the lower portion of thechamber, or to an external reservoir, and in a second position connectsthe liquid nozzle to an exterior source of liquid thus providing asmall, self-contained liquid supply or a connection to a substantiallylarger supply as desired. The control member comprises a core elementrotatably mounted in one housing end. Supported centrally on the core isthe air nozzle and supported radially on the core is the liquid nozzle.Passages are formed in the core to connect the air nozzle to an airsupply regardless of the rotative core position and to connect theliquid nozzle to the lower chamber portion or external liquid supplydepending on the rotative core position.

At the housing end opposite and distal from the core is the nebulizeroutput. Interposed between the output and the core is a baffle assemblyhaving a plurality of parallel spaced transverse discs of a diameterequal to the chamber diameter. Each disc has a chordal segment removedto form a passage for the vapor. The passages of adjacent discs arenonaligned so that the vapor flow through the baffle is in a tortuouspath against and along a plurality disc surfaces. It has been found thatthis baffle assembly is highly efficient and collapses vapor dropletsgreater than about 1/2 micron in diameter producing a mist that will notcohere or adhere, will go through bronchioles, and will not condense ona polished surface at ambient temperatures.

It is therefore an object of this invention to provide an improvednebulizer for providing a uniformly fine vapor.

Another object is to provide an improved nebulizer of the foregoingobject wherein the liquid to be nebulized may be self-contained in thenebulizer or in an exterior liquid container.

The above-mentioned and other features and objects of this invention andthe manner of attaining them will become more apparent and the inventionitself will be best understood by reference to the following descriptionof an embodiment of the invention taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially sectioned view of a preferred embodiment of thisinvention;

FIG. 2 is an end view of the embodiment of FIG. 1 as viewed from theright;

FIG. 3 is a section taken at 3--3 of FIG. 1;

FIG. 4 is a section taken at 4--4 of FIG. 1;

FIG. 5 is a view in perspective of the nozzle drum and support of FIG.1; and

FIG. 6 is a view in perspective of the baffle assembly used in theembodiment of FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to FIG. 1, elongated tubular housing 20 supports at one end 21a mounting ring 22 having annular sleeve 24 extending therefrom andforming shoulder 26 which is insertable in end 21 of housing 20 in atight frictional fit, end 21 of housing 20 abutting shoulder 26.Rotatably mounted in ring 22 is nozzle drum 28 having central bore 30and end flange 32. Drum plate 34 is secured to drum 28 by threadedfasteners 36, 38 threadedly received in drum 28. Flange 32 and plate 34serve to axially locate drum 28 on ring 22. Each of bolts 36, 38 haveprotruding heads which are used, as will become apparent, as fingeraccess surfaces to rotate drum 28 in ring 22.

Plate 34 has formed in the periphery thereof arcuate slot 40 having slotends 42, 44. As will become apparent, the length of slot 40 determinesthe rotative travel limits of drum 28 in ring 22, as shown by arrow 45.

Also formed in drum 28 is off-center axially parallel bore 46 which hasat one end thereof radially extending passage 48 which is registrablewith radially extending passage 50 in ring 22. Passage 50 has a smooth,tapered opening adapted to receive commercially available standardhypodermic syringe tip 52 of flexible plastic tube 53 connected toliquid container 54 which may be a soft intravenous bottle or pack.Container 54 may contain a liquid medicant, a radiopaque substance orother liquid which is to be nebulized for use in medical, radiography,industrial or other uses. Tube 53 may be of any desired length tofacilitate movement of housing 20 independently of container 54.

Also formed in drum 28 and in fluid communication with passage 46 ischordal passage 56 (FIG. 3) which extends between passage 46 and theexterior of drum 28. Passage 56 is registrable with radially extendingpassage 58 (FIG. 3) in sleeve 24 and axially parallel passage 60 insleeve 24 which communicates with the lower portion of chamber 62 inhousing 20.

Attached to the end of drum 28, as by an adhesive, is L-shaped support64 (FIG. 5) having leg 66 and base 68. Formed in leg 66 is axial passage70 which is aligned with passage 30 in drum 28 and supports tube 72which provides fluid communication between a pneumatic pressure source,not shown, through a flexible tube 74. A smooth, tapered opening 73receives hypodermic syringe tip 38 on tube 74. Tube 72 has a tapered end76 protruding into chamber 62 which forms an air nozzle. Axiallyparallel passage 78 is formed in base 68 and registers with passage 46in drum 28. Transverse passage 80 in base 68 extends from the inner endof passage 78 inwardly toward nozzle 76. Tube 82 is supported inpassages 48, 78, and 80 and has an opening therein approximately midwaythereof which communicates with passage 56. One end of tube 82communicates with tip 52. The other end 88 of tube 82 is closelyadjacent but not touching the horizontal diameter of nozzle 76 wherebyair flow through nozzle 76 of sufficient velocity will cause aspirationof liquid through tube 82 and nozzle 88. Air flow through nozzle 76 maybe controlled for optimum results in the various applications of thisinvention.

Pin 90 is fixedly supported in ring 22 and extends in an axiallyparallel direction from the end thereof in slot 40. Pin 90 incooperation with slot ends 42 and 44 determines the rotative travellimits of drum 28. In the angular rotative position shown in FIG. 2,slot end 42 is abutting pin 90, and passages 48 and 50 are aligned (FIG.4), and tube 82 is in communication with tip 52 of tube 53. Thecommunication between tube 82 and tubular passage 60 is interruptedsince passage 56 is unaligned with passage 58 (FIG. 3).

Rotating drum 28 counterclockwise until slot end 44 abuts pin 90, movespassage 48 to position 48a (FIG. 4) and the communication between tube82 and spout 52 is interrupted since passages 48 and 50 are no longeraligned. However, in this rotative position passage 56 is in position56a (FIG. 3) and communication between tube 82 and tubular passage 60 isestablished since passage 56 is now aligned with passage 60. The purposeof switching communication from passage 60 and spout 52 will becomeapparent as this description proceeds.

Located in an intermediate longitudinal position in housing 20 is baffleassembly 92. Baffle core 94 of assembly 92 supports three baffle discs96, 98, and 100. Each disc has a chordal section removed therefrom alongchordal lines 96a, 98a and 100a, (FIG. 6) to form disc openings. Chordallines on adjacent discs, such as between discs 96 and 98 are in anangular position such that the angle between the disc radii which areperpendicular to chords 96a and 98a are preferably slightly less than180°. When projected on a parallel plane, chordal lines 96a and 100aoverlie. In this manner, there are no overlapping disc openings andchordal lines of adjacent discs, when projected on a common plane, donot intersect in the disc area. By having the removed chordal sectionsso aligned, it is seen that any fluid passing axially through theinterior of housing 20 is caused to impinge upon disc surfaces as wellas the inner walls of housing 20 thereby collapsing any droplets in thefluid stream which are greater than about one-half micron in diameter.Substantially all of the droplets are collapsed on disc 100 and theexposed portion of disc 98, the chamber adjacent disc 96 remaining dry.

By having three discs 96 to 100, disc circumferences 96b and 100b are inspaced contact with one side of housing 20 and circumference 98b is incontact with an opposite side of housing 20 to provide stabilized discsupport. Preferably, the baffle is placed in housing 20 so that chords96a to 100a are at an angle with the horizontal transverse axis ofhousing 20.

A cap 106 has a boss 108 which is insertable in, and has a friction fitwith the inside end 109 of housing 20. Eccentric outlet opening 110 isformed in cap 106 and is non-aligned with the disc opening formed bychordal segment 96a to provide a final baffle stage for the nebulizedfluid. The baffling thus provided will cause a condensate liquidaccumulation in the lower portion of the chamber 62 in housing 20. Adrain opening 112 has a smooth, tapered opening for receiving syringetip 114 on tube 116 and is connected to reservoir 118. Alternatively, aplug may be inserted to capture and accumulate the condensate in thehousing interior chamber 62. If accumulated, the condensate will flowinto passage 60. If drum 28 is rotated to its counterclockwise position,a flow of air through pipe 74 and nozzle 76 will aspirate the collectedliquid through nozzle 88 from reservoir 118. Drum 28 may be rotated in aclockwise direction so that nozzle 88 is in fluid communication with thecontents of liquid container 54 for aspiration therefrom.

The nebulizer shown in FIG. 1 may also be used as a compact portableunit by removing liquid container 54, rotating drum 28 in itscounterclockwise position so that passage 56 is in communication withpassage 60, and by filling chamber 62 through port 112 to the desiredlevel with the liquid to be nebulized and then inserting a plug in port112. When used in this mode, the liquid level must not interfere withthe aspiration of the liquid from nozzle 88 and the contact between disccircumference 102 and the inner surface of housing 20 should besubstantially liquid-tight.

Importantly, the source of aspirated liquid, whether in container 54 orreservoir 118, is below the aspirating area of tube 76 and 88 to preventflooding and improper aspiration. The aspirated fluid is drawn upagainst gravity in the proper amount when the liquid is so positioned.The condensate which is collected in reservoir 118 may be reused forhumidifying and the like but should not be reused when the nebulizer isvaporizing a sterilized medicant from an intravenous sack or the like.When the liquid in reservoir 118 is to be reused, passage 119 isestablished, otherwise, passage 119 is effectively removed, as it wouldbe when a separate container 54 is used. Also, oxygen may be used as theaspirating fluid connected to the tube 74 and emitted from nozzle 76.Further, the nebulizer may be chemically cleaned and sterilized bymerely placing the desired cleaning liquid in reservoir 118 andcontainer 54 and aspirating in both positions of core 28. Additionally,various sized nebulizers may be used; smaller units may be desired foruse as inhalants and medicants and other medical uses while larger unitsmay be used for vaporizers or humidifiers or other large volumecontinuous uses.

While there have been described above the principles of this inventionin connection with specific apparatus, it is to be clearly understoodthat this description is made only by way of example and not as alimitation to the scope of the invention.

What is claimed is:
 1. Nebulizer apparatus comprising;an elongatehousing having a chamber therein and supporting a pneumatic nozzle inaspirating relation to a liquid nozzle in said chamber; a liquid inletformed in said housing in fluid communication with said liquid nozzle; apneumatic inlet formed in said housing in fluid communication with saidpneumatic nozzle; a liquid passage between said chamber and said liquidnozzle; and flow control means for selectively connecting said liquidnozzle to one of said liquid inlet and liquid passage and comprising; adrum rotatably mounted at one end of said housing; said pneumatic inletcomprising a first axial passage; said drum having an eccentric axialpassage parallel with said first axial passage and connected to a firsttransverse passage terminating in said liquid nozzle; said liquid inletcomprising a second transverse passage in fluid communication with saideccentric passage; and said liquid passage comprising a third transversepassage in fluid communication with said eccentric passage and angularlydisplaced from said second transverse passage.
 2. A nebulizer accordingto claim 1 including:a stop element fixed to said housing; said drumhaving means registerable with said element and cooperating therewithfor defining first and second rotational limits of said drum; said drumat said first limit connecting said liquid inlet to said liquid nozzleand at said second limit connecting said liquid passage to said liquidnozzle.
 3. A nebulizer according to claim 2 wherein said drum has acoaxial passage therein in fluid communication with said first axialpassage and said pneumatic nozzle.
 4. A nebulizer according to claim 3wherein said housing has a drain opening having a removable closuretherein.
 5. A nebulizer according to claim 6 including means forconnecting a liquid container to said housing in fluid communicationwith said liquid inlet.
 6. A nebulizer according to claim 5 wherein saidhousing has an end cap distal from said drum snugly mounted in vaporsealing relation to said distal end; said end cap having an eccentricvapor outlet to form a final baffle stage.
 7. A nebulizer according toclaim 6 further comprising:a plurality of planar baffle members mountedin spaced relation in said housing; each member having a surface portionremoved therefrom to form an opening; the openings of two adjacentmembers having non-overlapping portions whereby fluid flowing throughone opening will impinge on the surface of the adjacent member andchange fluid direction collapsing liquid droplets on said bafflesurface.